Deep in the wet forests of southeastern Australia, something starts singing that sounds like several birds at once.
Then comes a dog.
Then another bird.
Then something that sounds strangely mechanical.
If you are standing in the forest and cannot see the source, it can be difficult to work out what you are actually listening to. The singer is a superb lyrebird, and one of the most unusual vocal mimics in the animal world.
But copying sounds is only part of the story.
The lyrebird spends much of its life walking through leaf litter, scratching at the forest floor with powerful feet, searching for insects and other small prey. It rarely flies. The male builds display mounds, spreads a spectacular tail over his back, and sings an acoustic performance that can contain sounds borrowed from the world around him.
The strange thing is that some of those sounds are almost perfect copies.
There Are Only Two
Lyrebirds belong to the family Menuridae, and there are only two living species: the superb lyrebird, Menura novaehollandiae, and Albert's lyrebird, Menura alberti.
Both are found only in Australia.
The superb lyrebird has the larger distribution. It occurs across wet forests of southeastern mainland Australia, including parts of Victoria, New South Wales and southeastern Queensland. It was also introduced to Tasmania in the 1930s.
Albert's lyrebird has a much smaller range. It is restricted to subtropical rainforest and moist forest in southeastern Queensland and northeastern New South Wales, including areas around the McPherson, Tweed and Richmond ranges and Lamington National Park. Some populations occur at elevations above about 300 meters in areas of high rainfall.
The two species look related because they are, but they are not identical.
Albert's lyrebird is darker and more brown or chestnut in color, while the superb lyrebird is generally greyer. The male superb lyrebird also has the dramatic tail that gave the group its name.
Lift that tail over the body and the long feathers resemble an old musical instrument called a lyre.
That is where "lyrebird" comes from.
A Large Bird That Prefers the Ground
The superb lyrebird is a surprisingly large songbird.
Adult males can weigh around 1 kilogram, sometimes slightly more, while females are generally lighter. Males can reach roughly 80–98 centimeters in total body length, although much of that impressive measurement comes from the tail.
For such a large bird, it is an odd choice to spend so much time walking.
Lyrebirds are ground-dwelling birds of moist forests. They scratch through fallen leaves looking for earthworms, beetles, cockroaches, spiders, centipedes, larvae and other invertebrates. Seeds can also form part of the diet, and small vertebrates such as frogs and lizards are occasionally eaten.
The feet are built for this job.
A lyrebird can rake through the leaf litter, moving leaves aside with quick, powerful movements while searching underneath.
This constant disturbance also has an effect on the forest floor. Lyrebirds can turn over large amounts of leaf litter and soil while feeding, influencing nutrient movement and seed distribution.
So while the bird looks like a singer, much of its working day is spent behaving more like a small forest excavator.
The Tail Is Not Just Decoration
The male's tail is the feature most people notice first.
A fully developed superb lyrebird tail contains several different types of feathers. The long outer feathers and central plumes create the distinctive lyre shape when the male raises the tail above his body.
But the tail does not appear overnight.
Young males take years to develop the full adult plumage. Museum Victoria notes that males may take around six to eight years to develop the complete adult tail.
That is a long investment for a bird.
And it is connected to another investment that takes even longer: learning how to sing.
The Forest Gets Copied
This is where the lyrebird becomes famous.
A male superb lyrebird can imitate the calls and songs of other birds with extraordinary accuracy.
But he does not simply memorize one sound and repeat it forever.
His song can be a collection of different sounds assembled into a long performance.
The Australian Museum estimates that around 80 percent of the superb lyrebird's song can consist of mimicry. The sounds may include native birds as well as noises produced by animals and human activity, including dogs, car engines and chainsaws.
That last part is especially strange.
A lyrebird does not have to understand what a chainsaw is to copy its sound.
It only has to hear it.
Researchers have documented superb lyrebirds mimicking remarkably different sounds, and studies have shown that the imitation of other birds can be extremely accurate.
In one experiment published in Animal Behaviour in 2012, researchers tested lyrebird imitations of the grey shrike-thrush. The copies were accurate enough that the shrike-thrushes often responded to the recordings almost as they responded to the real species. Acoustic analysis also showed that some imitations were extremely close to the original sounds.
That is not just a bird making a vague impression of another bird.
It is copying the sound closely enough to fool the bird being copied.
But Why Copy Anything?
This is where the story gets more interesting.
For years, scientists have debated exactly what lyrebird mimicry is for.
It is tempting to imagine that the male is simply showing off his enormous memory.
There is more going on than that.
Male superb lyrebirds use mimicry as part of their sexual displays, and recent research suggests that different parts of their performances may serve different purposes.
A 2022 study in Animal Behaviour examined recordings of male superb lyrebirds during the breeding season. Researchers found that males used different types of mimicked sounds during different display situations.
During their acoustic "recitals," males mimicked a variety of bird songs and calls. During the more unusual audiovisual dance display, the males concentrated heavily on mimicking alarm calls.
That is important because it suggests the song is not simply a random collection of sounds.
The male is making choices.
Exactly why particular sounds are chosen is still not completely understood, but researchers have found consistent patterns in the sounds males imitate.
In other words, the lyrebird's famous ability is impressive.
The really interesting question is what the bird is doing with it.
The Song Takes Practice
Young lyrebirds do not emerge from the nest as perfect mimics.
Their vocal performance develops over time.
A 2008 study compared superb lyrebirds from different populations and age groups. Researchers found that younger birds produced poorer copies and fewer recognizable mimicked song elements than adults. The study also found differences between geographically separated populations in the sounds that males used and how frequently they repeated particular models.
That means the song is partly learned.
A young male grows up surrounded by the sounds of his forest.
He hears other birds.
He hears lyrebirds.
He hears the local acoustic environment.
And over the years, he develops his own version of the performance.
This may help explain why lyrebird songs can vary between places.
A bird in Victoria is not necessarily learning exactly the same acoustic material as one hundreds of kilometers away in New South Wales.
The Famous Chainsaw Problem
There is a persistent story about lyrebirds copying chainsaws, cameras and other machinery.
The basic idea is real.
Researchers have documented superb lyrebirds reproducing anthropogenic sounds, and captive males have been recorded imitating sounds such as camera shutters, emergency sirens, chainsaws and even human baby cries.
But there is an important detail that often gets lost online.
These unusual sounds are not necessarily the normal core of a wild lyrebird's song.
In the wild, the bird's vocal performance is strongly connected with its biological and social environment. Native bird calls make up an important part of what males imitate.
The chainsaw makes a great story because it is strange to human ears.
For the lyrebird, it is simply another sound it has encountered.
A Courtship Performance on a Mound
During breeding season, the male does not just stand on an ordinary patch of forest floor and sing.
He uses display mounds.
These are areas of ground that the male prepares or maintains within his territory. From there, he sings and performs, sometimes lifting his enormous tail over his body and shaking it as part of the display.
Females visit the males and choose among them.
The male may mate with several females, while the female takes responsibility for building the nest and raising the young.
The breeding season varies somewhat across the range, but breeding generally occurs during the cooler months. In many populations, display and breeding activity peaks around May to August or extends into the June–October period depending on location.
This is another reason the male's long tail makes sense.
It is not an ornament designed for human admiration.
It is part of a courtship system that has been shaped by sexual selection.
One Egg, Then a Long Wait
The female builds a large, dome-shaped nest using sticks, moss, ferns, feathers and other plant material.
The nest can be hidden close to the ground, sometimes among vegetation, on banks, in tree stumps, or other sheltered locations.
Usually there is only one egg.
That is a remarkably small clutch for a bird this size.
The egg takes roughly six weeks to hatch, and the chick remains in the nest for several more weeks before becoming independent enough to leave. New South Wales wildlife authorities report that the young bird can remain in the nest for around 6–10 weeks.
The female does the work.
The male's role is largely about territory and courtship rather than raising the chick.
That makes the spectacular male display look a little different.
All that singing and dancing happens while the female is preparing for a very long period of parental investment.
They Are Not Great Flyers
There is something almost comical about a bird this large having such limited flying ability.
Lyrebirds have short, rounded wings and spend most of their time on the ground.
When threatened, they would rather run.
They can move quickly through dense vegetation, weaving between trees and undergrowth where a larger predator may have difficulty following.
The wings are still useful. A lyrebird can jump onto a branch or rock and glide back toward the forest floor, and at night it usually roosts in trees.
But if you are hoping to see a lyrebird soaring over the Australian forest, you are probably looking in the wrong place.
Look down.
Then listen.
The Forest Is Part of the Song
Superb lyrebirds are strongly associated with moist forests, rainforests and wet eucalypt forests.
Research in Victoria has shown that their nesting and foraging activity is influenced by detailed features of the forest, including deep leaf litter, vegetation structure and proximity to creeks. Nest sites were more likely to occur in wet forest or rainforest close to creek lines, while foraging activity was associated with particular conditions on the forest floor.
This makes sense once you understand how the bird lives.
The lyrebird needs the forest floor for food.
It needs dense vegetation for cover.
It needs trees for roosting.
And the male needs suitable ground on which to perform.
The bird is not simply living inside the forest.
Its behavior is tied closely to the structure of the forest itself.
When the Forest Changes
The superb lyrebird is currently listed as Least Concern globally, but that does not mean every population faces exactly the same conditions.
Habitat destruction, fragmentation, introduced predators and severe fires can affect lyrebirds, particularly because they spend so much time on or near the ground.
Albert's lyrebird is more vulnerable to local habitat changes because its distribution is much smaller. Its range is concentrated in rainforest and moist forest around the Queensland–New South Wales border, with an isolated population at Tamborine Mountain. Fire, habitat fragmentation and introduced predators such as cats and foxes are among the concerns identified for the species.
For a bird with a restricted range, losing a small piece of suitable forest can matter much more than it would for a species spread across an entire continent.
The Bird That Records Its Neighborhood
The strangest thing about a lyrebird may not be its tail.
It may be its memory.
A male spends years developing a vocal performance made partly from sounds he has heard around him. His song can contain the voices of other species, and sometimes sounds created by people.
In that sense, a lyrebird carries a small acoustic record of its surroundings.
The forest teaches it what to sing.
The other birds provide material.
The landscape shapes the performance.
And the male turns all of it into something that is recognizably his own.
That is why hearing a lyrebird in an Australian forest is different from simply hearing a bird call.
You may be listening to several species at once.
And if there happens to be a chainsaw somewhere in the neighborhood, there is a chance the lyrebird has been listening too.
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